angina (an-JY-nuh): People with angina feel a
pain in the chest that means the heart isn't getting enough oxygen.

angioplasty (AN-jee-uh-plas-tee): This operation
opens a blocked blood vessel by using a balloon-like device at an artery's narrowest
point. The surgeon also may insert a stent, which is a tiny tube that props the vessel
open and makes sure that blood can flow freely through it.

aorta (ay-OR-tah): The aorta is the major blood
vessel that carries blood away from the heart to the rest of the body.

aortic stenosis (ay-OR-tik steh-NOH-sis): This
is when the aortic valve is stiffened and has a narrowed opening (stenosis).
It does not open properly, which increases strain on the heart because the left ventricle
has to pump harder to send blood out to the body.

aorticvalve: The aortic valve is one of two
valves that control the flow of blood as it leaves the heart. (The other is the pulmonary
valve.) These valves work to keep the blood flowing forward. They open up to let the
blood move ahead, then close quickly to keep the blood from flowing backward.

arrhythmia (uh-RITH-mee-uh):
An arrhythmia is an abnormal heartbeat usually caused by an electrical "short circuit"
in the heart. It can cause the heart to pump too fast, too slow, or irregularly, which
may lead to shortness of breath, dizziness, and chest pain.

arteriesandveins: As part
of the circulatory system, these help the body send blood to and from your body
parts. Arteries, which usually look red, carry blood away from the heart. Veins, which
usually look blue, return blood to the heart.

arteriosclerosis (ar-TEER-ee-oh-skluh-ROH-sus): Also
called hardening of the arteries, arteriosclerosis means the arteries become thickened
and less flexible.

atria (AY-tree-uh): The two chambers at
the top of the heart are called the atria. The atria are the chambers that fill with
the blood returning to the heart from the body and lungs. The heart has a left atrium
and a right atrium.

atrialseptal (AY-tree-uhl SEP-tuhl) defect
(ASD): ASD is a hole in the heart wall
(called the septum) that separates the left atrium and the right atrium.

atrioventricular (AY-tree-oh-ven-TRIK-yoo-lar) canaldefect: This defect — also known
as endocardial cushion defect or atrioventricular septal defect — is caused
by a poorly formed central area of the heart. Typically, there is a large hole between
the upper chambers of the heart (the atria) and, often, an additional hole between
the lower chambers of the heart (the ventricles). Instead of two separate valves allowing
flow into the heart, there is one large common valve that might be quite malformed.

atrium (AY-tree-uhm): The two
upper chambers of the heart are called the atria. They are the chambers that fill
with the blood returning to the heart from the body and lungs. The heart has a left
atrium and a right atrium.

bacterial endocarditis (bak-TEER-ee-ul en-doh-kar-DYE-tus): This
infection in the heart happens when bacteria travel through the blood and get
stuck on a heart valve. People with congenital heart disease or heart valve problems
are most at risk of getting bacterial endocarditis.

blood pressure: This is a measurement that tells how hard the
heart is pumping to move blood through the blood vessels. Blood pressure can be too high or too low.

blood vessels: Blood moves through many tubes called arteries
and veins, which together are called blood vessels. The blood vessels that carry blood
away from the heart are called arteries. The ones that carry blood back to the heart
are called veins.

capillary (KAP-ih-lair-ee): A
capillary is an extremely small, thin blood vessel that allows oxygen to pass from
the blood into the tissues of the body. Waste products like carbon dioxide pass from
the tissues to the blood through the capillaries.

cardiac catheterization
(KAR-dee-ak ka-thuh-ter-uh-ZAY-shun): A cardiac catheterization
is a medical procedure that provides information about the heart structures and function.
Doctors can measure pressure and blood oxygen levels within the heart chambers.

cardiologist (kar-dee-AHL-uh-jist): This doctor
specializes in diagnosing and treating heart conditions, like heart murmurs and high blood
pressure. A pediatric cardiologist cares for babies, children, and teens with
heart problems.

cardiovascular (kar-dee-oh-VAS-kyuh-ler)disease: Cardiovascular
disease is a group of problems that occur when the heart and blood vessels aren't
working properly.

cardiovascularsystem:The
heart and circulatory system (also called the cardiovascular system) make up the
network that delivers blood to the body's tissues. With each heartbeat, blood is sent
throughout our bodies, carrying oxygen and nutrients to all of our cells. The cardiovascular
system is composed of the heart and blood vessels, including arteries, veins, and
capillaries.

carotid (kuh-RAH-tid) artery: The carotid arteries
are the two large blood vessels in the neck that supply blood to the brain.

catheter (KA-thuh-ter): A
catheter is a thin, flexible tube. It can be inserted into a blood vessel in
the leg, arm, or neck and threaded to the heart during a cardiac catheterization.

catheterization
(ka-thuh-tur-uh-ZAY-shun): In this procedure, a long, thin tube
is inserted into the patient's body to inject a special dye, which can show narrowed
areas in arteries due to plaque buildup and find other heart problems.

chambers: The heart has four different sections, or chambers.
These chambers are connected to each other by valves that control how much blood enters
each chamber at any one time.

circulation (ser-kyuh-LAY-shun): The
movement of the blood through the heart and around the body is called circulation.
The heart takes less than 60 seconds to pump blood to every cell in your body.

circulatory (SER-kyuh-luh-tor-ee) system:The circulatory system is composed of the heart
and blood vessels, including arteries, veins, and capillaries. Our bodies actually
have two circulatory systems: The pulmonary circulation is a short loop from the heart
to the lungs and back again, and the systemic circulation (the system we usually think
of as our circulatory system) sends blood from the heart to all the other parts of
our bodies and back again.

coarctation (coh-ark-TAY-shun) of the aorta
(COA): Coarctation of the aorta is a narrowing
of a portion of the aorta, and often seriously decreases the blood flow from the heart
out to the lower portion of the body.

congenital (kuhn-JEN-ih-tuhl) heart
defects:Congenital
heart defects are abnormalities in the heart's structure that are present at birth.
They happen because of incomplete or abnormal development of the fetus' heart during
the very early weeks of pregnancy. Some are known to be associated with genetic disorders,
such as Down syndrome, but the cause of most congenital heart defects is unknown.
While they can't be prevented, there are many treatments for the defects and related
health problems.

contraction (kuhn-TRAK-shun): You'll
know that you've found your pulse when you can feel a small beat under your skin.
Each beat is caused by the contraction (squeezing) of your heart.

echocardiogram (eh-ko-KAR-dee-uh-gram): An
echocardiogram test uses sound waves to diagnose heart problems. These waves are bounced
off the parts of the heart, creating a picture of the heart that is displayed on a
monitor.

electrocardiogram (eh-lek-tro-KAR-dee-uh-gram): An
electrocardiogram (also called an EKG or ECG) test records the heart's
electrical activity. Sticky pads (electrodes) are placed on the chest and hooked up
to a machine that records the heart activity onto paper or a monitor. A doctor can
interpret the EKG to see the heart beating and determine if it's normal.

endocarditis (en-doh-kar-DYE-tis): An infection
of the inner lining of the heart and heart valves.

heart: The heart is a strong
muscle about the size of your fist. It pumps blood through blood vessels around the
body and sits inside the chest, protected by the ribcage. The blood carries oxygen
and other nutrients your body needs.

heart and circulatory system:
The heart and circulatory system (also called the cardiovascular system) make up the
network that delivers blood to the body's tissues. With each heartbeat, blood is sent
throughout our bodies, carrying oxygen and nutrients to all of our cells. The circulatory
system is composed of the heart and blood vessels, including arteries, veins, and
capillaries.

heart attack: A heart attack happens when a blood clot or other
blockage cuts blood flow to a part of the heart.

heart murmur: You
know the sound of your heartbeat: lub-dub, lub-dub. In some people, there's an extra
noise that the blood makes as it flows through the heart. This sound is called a murmur.
They're commonly heard in healthy kids with normal hearts, but an abnormal heart murmur
can mean a person has a heart defect or heart valve problem.

hypoplastic (hi-poh-PLAS-tik) left heart syndrome: When
the structures of the left side of the heart (the left ventricle, the mitral valve,
and the aortic valve) are underdeveloped, they're unable to pump blood adequately
to the entire body. This condition is usually diagnosed within
the first few days of life.

involuntary (in-VOL-un-tair-ee) muscles: These
are muscles that we do not consciously control. They work without us even thinking
about them. The heart is an involuntary muscle, which is how it keeps beating all
day and night. Involuntary muscles in the stomach and intestines help us digest food.

left atrium: The left atrium is one of the four chambers of the
heart. It receives oxygen-rich blood from the lungs and then empties the blood into
the left ventricle through the mitral valve.

left ventricle: The left ventricle is one of the four chambers
of the heart. It pumps oxygen-rich blood out to the rest of the body. Blood leaves
the left ventricle through the aortic valve and enters the aorta, the largest artery
in the body. Blood then flows from the aorta into the branches of many smaller arteries,
providing the body's organs and tissues with the oxygen and nutrients they need.

patent ductus arteriosus
(DUK-tuss ar-tee-ree-OH-sis) (PDA): The ductus arteriosus (DA)
is a normal blood vessel in an unborn baby that diverts blood flow away from the lungs.
(The lungs are not used until a baby is born — the fetus gets oxygen directly
from the mother's placenta.) The DA usually closes on its own shortly after birth
because the newborn can breathe on his or her own. If the DA doesn't close, this is called
patent ductus arteriosus (PDA), which can result in too much blood flow to a newborn's
lungs. PDA is common in premature babies.

pediatric cardiologist: Children with heart problems are cared
for by pediatric cardiologists. They treat all kinds of heart problems, from
heart murmurs to high blood pressure.

pulmonary (PULL-muh-nair-ee): Pulmonary is word
that means lungs or related to breathing.

pulmonary artery: A blood vessel that carries blood from the heart
to the lungs, where the blood picks up oxygen and then returns to the heart.

pulmonary vein: One of four veins that carry oxygen-rich blood
from the lungs to the heart.

pulmonary atresia (uh-TREE-zhuh):
In this birth defect, the pulmonic valve does not open or is completely missing.
The main blood vessel that runs between the right ventricle and the lungs also may
be malformed and the right ventricle can be abnormally small.

pulmonary stenosis (steh-NOH-sis): In pulmonary
stenosis, the pulmonic valve is stiffened and has a narrowed opening. It does not
open properly, which increases strain on the right side of the heart because the right
ventricle has to pump harder to send blood out to the lungs.

pulmonary (pulmonic) valve: One of two valves in
charge of controlling the flow as the blood leaves the heart. The other one is the
aortic valve. These valves all work to keep the blood flowing forward. They open up
to let the blood move ahead, then they close quickly to keep the blood from flowing
backward.

pulse: A beating heart creates a pulse. The heart has to push
so much blood through the body that we can feel a little thump in our arteries each
time the heart beats. The most common places to feel a pulse are on the wrist and
the neck.

red blood cells: Red blood cells carry oxygen. They float in the
blood, begin their journey in the lungs, where they pick up oxygen from the air we
breathe. Then they travel to the heart, which pumps out the blood, delivering oxygen
to all parts of the body.

right atrium: The right atrium is one of the four chambers of
the heart. After oxygen in the blood is released to the tissues, the now deoxygenated
(oxygen-poor) blood returns to the heart through veins, the blood vessels that carry
deoxygenated blood. This blood, which appears blue, enters the right atrium of the
heart and then travels across the tricuspid valve into the right ventricle.

right ventricle: The right ventricle is one of the four chambers
of the heart. It pumps deoxygenated blood through the pulmonic valve into the lungs.
The oxygen in the air we breathe binds to red blood cells that are being pumped through
the lungs. The oxygen-rich blood, which appears red, then returns to the left atrium
and enters the left ventricle, where it is pumped out to the body once again.

septum (SEP-tum): The septum is a thick wall
of muscle that divides the heart. It separates the left and right sides of the heart.

stent: A tiny tube that props a blood vessel open and helps blood
flows freely.

stethoscope (STETH-eh-skope): The instrument
doctors use to hear a heartbeat and other sounds that the inside of the body makes.
By listening to the heart, lungs, and belly, the doctor gets information about how
things are working inside.

stress test: For this test, a person exercises (usually on a treadmill)
while the doctor checks breathing, heart rate, blood pressure, and electrocardiogram
to see how the heart muscle reacts.

stroke: A stroke can happen
when part of the brain doesn't get enough blood due to a clot or a burst blood vessel.

tricuspid (try-KUS-pid) atresia: Blood normally
flows from the right atrium to the right ventricle through the tricuspid valve. In
tricuspid atresia, the valve is replaced by a plate or membrane that does not open.
The right ventricle therefore does not receive blood normally and is often small.

tricuspidvalve: The tricuspid valve lets blood
flow from the right atria to the right ventricle.

truncus arteriosus (TRUN-kuss ar-tee-ree-OH-sis): In
an embryo, the aorta and the pulmonary artery are initially a single vessel. During
normal development, that vessel splits to form the two major arteries. If that split
does not occur, the child is born with a single blood vessel called the truncus arteriosus.
There is usually a hole between the ventricles associated with this defect.

valve: The heart has four valves. These valves ensure that blood
flows properly in and out of the heart.

veins and arteries: As part of the circulatory system, these
help the body send blood to and from your body parts. Arteries, which usually
look red, carry blood away from the heart. Veins, which usually look blue, return
blood to the heart.

ventricles (VEN-trih-kuhls): The two chambers
at the bottom of the heart are called the ventricles. The heart has a left ventricle
and a right ventricle. Their job is to pump the blood to the body and lungs.

ventricular (ven-TRIK-yuh-ler) septal defect (VSD):
One of the most common congenital heart defects, VSD is a hole in the wall (septum)
between the heart's left and right ventricles. These can happen at different locations
and vary in size from very small to very large. Smaller defects may gradually close
on their own.

white blood cells: White blood cells are part of the germ-fighting
immune system. They are like little warriors waiting to attack invaders, such as viruses
and bacteria. The body has several types of white blood cells and each has its own
role in fighting off the different kinds of germs that make people sick.